Occurrence of free and conjugated Fusarium mycotoxins in cereal-based food

A collection of 84 cereal-based food products in 25 composites, including beer, was screened for the presence of deoxynivalenol, zearalenone, and their respective metabolites deoxynivalenol-3-glucopyranoside, 3-acetyl-deoxynivalenol, zearalenol-4-glucopyranoside, alpha-zearalenol, beta-zearalenol, alpha-zearalenol-4-glucopyranoside, beta-zearalenol-4-glucopyranoside, and zearalenone-4-sulfate. The most abundant analyte was zearalenone-4-sulfate, which was found in 13 composites, albeit in low concentrations. Furthermore, deoxynivalenol was detected in eight, zearalenone in seven, and deoxynivalenol-3-glucopyranoside in two composites. None of the remaining six analytes was found in any matrices, which suggests that, if at all present, the concentrations of these latter metabolites are very low and, hence, do not impose any danger to consumers. The highest mycotoxin content was found in bran flakes with 254 ng g(-1) deoxynivalenol, 6 ng g(-1) zearalenone-4-sulfate, and 44 ng g(-1) zearalenone.